what does garbage collected mean
 

i've heard of languages that are garbage collected. i think java is an
example. what does this mean

its a method to reclaim memory, from unused objects.. more or less.
read this
java has automatic collection, c++ might be manual... im not positive, i dont use c++, only java.

C / C++ certainly do not have Garbage Collection.

Ass far as I know, it is to free up memory on the heap from unused objects. I think it also has something to do with pointers - If you dynamically allocate an array using malloc or calloc, you must remember to use free to release the memory.

Java does have automatic garbage collection - when there are no references to any objects, Java knows that it can safely remove these from memory, and will do so when it feels like it.

I hope this helps
--Ian

In C++ this function would cause a memory leak:

It generates a memory leak because the string "Hello World" is allocated on the heap. Pointer 's' is created on the stack when the function is called. s points to "Hello World", but s is lost when the function returns. Basically s was the last reference to this heap memory, and now it wont be found and a memory leak occurs. Java would notice this lack of references and perform the cleanup itself, probably by calling the string destructor when all references are destroyed.